Problem: Khan.scratchpad.disable(); For every level Luis completes in his favorite game, he earns $620$ points. Luis already has $250$ points in the game and wants to end up with at least $3560$ points before he goes to bed. What is the minimum number of complete levels that Luis needs to complete to reach his goal?
Explanation: To solve this, let's set up an expression to show how many points Luis will have after each level. Number of points $=$ $ $ Levels completed $\times$ Points per level $+$ Starting points Since Luis wants to have at least $3560$ points before going to bed, we can set up an inequality. Number of points $\geq 3560$ Levels completed $\times$ Points per level $+$ Starting points $\geq 3560$ We are solving for the number of levels to be completed, so let the number of levels be represented by the variable $x$ We can now plug in: $x \cdot 620 + 250 \geq 3560$ $ x \cdot 620 \geq 3560 - 250 $ $ x \cdot 620 \geq 3310 $ $x \geq \dfrac{3310}{620} \approx 5.34$ Since Luis won't get points unless he completes the entire level, we round $5.34$ up to $6$ Luis must complete at least 6 levels.